Official Google Play Help Page explains it as follows:
Q: What is Google Play?
A: Google Play is a new digital content
experience from Google where you can find your favorite music,
movies, books, and Android apps and games.
Q: When will I get Google Play? What markets is this available in?
A: We’ll be rolling out Google Play globally starting today. On the
web, Google Play will be live today. On devices, it will take a few
days for the Android Market app to update to the Google Play Store
app. The music, books and movies apps will also receive an update
Around the globe, Google Play will include Android apps and games. In
countries where we have already launched music, books or movies, you
will see those categories available in Google Play, too.
Q: I live outside the US. When will I get the books, music or movies verticals? I only see Android apps and games? A: We want to bring
different content categories to as many countries as possible. We’ve
already launched movies and books in several countries outside the
U.S. and will continue to do so overtime, but we don’t have a
specific timeline to share.
Q: What types of content are available in my country?
- Paid Apps: Available in these countries
- Movies: Available in US, UK, Canada, and Japan
- eBooks: Available in US, UK, Canada, and Australia
- Music: Available in US
You may check out the link for more info.